CA1254462A

CA1254462A - Method and structure of preventing cylinder head warpage, and over-heating of internal combustion engines

Info

Publication number: CA1254462A
Application number: CA000491730A
Authority: CA
Inventors: John R. Hilts
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-02-01
Filing date: 1985-09-27
Publication date: 1989-05-23
Also published as: US4545101A

Abstract

ABSTRACT
This invention relates to a method and struc-ture of preventing cylinder head warpage and over-heating of internal combustion engines by utilizing a cylinder head modification assembly. The cylinder head modi-fication assembly includes 1) a main expansion transfer plate assembly; and 2) an exhaust port expansion transfer assembly, each of which are adapted to be mounted on a cylinder head structure to provide strengthen-ing and expansion transfer characteristics. The main expansion transfer plate assembly is of an elongated rectangular shape having various portions of different heights in order to achieve the required strength and heat transfer properties. The exhaust port expansion transfer assembly includes a main support body having an integral anchor section and is adapted to be mounted and secured between adjacent exhaust ports of the cyl-inder head structure. These elements are attached to the existing cylinder head structure after slight modification thereof so as to distribute excessive ex-pansion build up and warpage during usage. The method of this invention involves the steps of preventing cylinder head warpage and over-heating by a machining process and application of the cylinder head modifica-tion assembly to a cylinder head structure.

Description

This invention relates to method and struc-ture of preventing cylinder head warpage, and over-heating of intern~l combustion engines. More specif-ically this invention is related to a method and struc-5 ture of preventing cylinder head warpage and over-heating of internal combustion engines and is divided ~
into the invention being a structure of 1) a cylinder head modification assembly; and 2) a method of pre-venting cylinder head warpage caused by localized over-10 heating. This invention is to be applied to a cylinder head structure which is part of an internal combustion engine which channels the exhaust gases from the com-bustion chambers and, perhaps due to deflector design, creates~excessive localized heat and resultant cylinder 15 head structure warpage.
This invention can be applied to an~ internal combustion engine having similar adjacent exhaust ports ~nd excessive heat pro~lems. A specific example of this problem is in an automobile known as the "Triumph 20 Stag" which was powered with a V-8 engine in approxi- -~
mately 1971-1972. From 1975 to 1980, the manufacturer sold a "Triumph Tr7" which was powered by a four-cylinder engine. The problems with the four-cylinder engine as noted herein is that the exhaust ports, es-25 pecially the inner ones, are adjacent to each other and , 5~L6'~
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thereore create excessive heat problems. More specif-ically, is that the cylinder head structur~ becomes loose from the engine block due to the excessive heat causing leakage of oil and coolant past a cylinder S head gasket. Eventually, this allows the coolant level to become low enough to cause extreme overheating con-ditions in the cylinder head structure thus allowing the same to warp. This occurs easily because the cylinder head structure is constructed of an aluminum material.
This over-heating and warpage is mainly caused due to a cylinder head design in which the exhaust valves for the center two cylinders are placed adjacent to each other.
This localized over-heating results in expansion and causes a compression of the softer aluminum material around the standard size steel washer and mounting bolts as a cylinder head temperature increases. Thus, when the engine is cooled, there is a gap between the steel washer and the cyl-inder head structure thus leaving the mounting bolts loose which now causes a gap and allows for the leakage of cool-ant fluid and oil therefrom.
U. S. Patent No. 2,361,106 discloses a method of repairing and for preventing cracks in metal castings, but is not related to the problem of preventing cylinder head warpage.
U. S. Patent No. 2,944l336 relates to the method of preventing thermal damage in combustion region wall structure of internal combustion engines similar to the purpose of the applicant's invention.
The object of this invention is to provide a method of preventing cylinder head warpage and overheating.
I The present invention further provides a method of preventing cylinder head warpage and over-heating of internal combustion engines, comprising:
a) applying an exhaust port expansion transfer assembly to an intermediate connector section above exhaust channels on said cylinder head structure, and ., .,~ ,. .
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b) securing said exhaust port expansion trans-fer assembly against said intermediate connec-tor section;
whereby said exhaust port expansion transfer assembly transfers heat from said intermediate connector section to control expansion and prevent warpage of said cylin-der head structure.
The present invention also provides a method of preventing cylinder head warpage and over-heating of in-ternal combustion engines, comprising:
(a) removing anchor bolt members that are ~olding a cylinder head structure against a cylinder block st~ucture;
(~) applying an expansion transfer plate assembly to an area above the exhaust ports on said cylinder head structure;
~c) inserting bolt members through holes in said main expansion tran~fer plate assembly so as to anchor same against said cylinder head structure and to said engine block structure; and d) torquing said bolt members to an even desired pressure ~o clamp said expansion transfer plate assembly against said cylinder head structure;
whereby said expansion transfer plate assembly applies a large surface area to an upper surface of said cylinder head structure to eontrol expansion and to prevent warpage thereof.
The cylinder head modification assembly can be readily attached to new or existing cylinder head struc-tures in a fast, simple manner not requiring special fix-tures or tools to do so. The assembly is easy to manufac-ture~ simple to install, and maintenance free.
In the dra~ings:
Figure l is a perspective view of à-cylinder head struc~ure to which the method and structure of the ' inven~ion herein is t~ utilized thereon;

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Figure 2 is a ~op plan view of an exhaust port expansion transfer assembly of a cylinder head modii-cation assembly of this invention;
Figure 3 is a side elevational view taken along line 3-3 in Figure 2;
Figure 4 is a top plan view of a main expansion transfer plate assembly of the cylinder head modi~ication assembly o this invention;
Figure 5 is an enlarged sectional view taken along line 5-5 in Figure 4;
Figure 6 is an enlarged sectional view taken alo~g line 6-6 in Figure ~i Figure 7 is an enlarged sectional view taken along line 7-7 in Figure 4;
Figure 8 is an enlarged ragmentary sectional view taken along line 8-8 in Figure l;
Figure 9 is a perspective view of a cylinder head structure having the cylinder head modification assem-bly and method of this invention as applied thereto; and Figure 10 is a schematic diagram illustrating the expansion transfer and strengthening characteristics o~
this invention.

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In ~.igure 9, a cylinder head mod:ification a~-sembly 12 of this invention is shown as applied to a cylinder head structure 14 of an internal combustion engine block 15 and secured thereto in a conventional 5 manner by a plurality of washers and bolt meI~ers 17.
Figure 1 shows a substantially conventional cylinder head structure 14 which is secured to an engine block structure, the cylinder head has many ports therein to transfer the exhaust gases outwardly 10 into a manifold assel~ly and then to a muffler struc-ture ~not shown). The cylinder head structure 14 in-cludes a main head body 16 of generally irregular shape.
The main head body 16 is provided with an up-per connector section 18; an exhaust gas section 20;
15 an intermediate connector section 22; and a lowe~..~on-nector section 24. The upper connector section 18 in-cludes a plurality of connector holes 26 adapted to re-ceive thé bolt and washer members 17 therethrough for anchoring the same to the engine block 15.
The exhaust gas section 20 includes a plur-ality of exhaust ports 28 which receive exhaust gases from exhaust channels 30. The exhaust channels 30 are divided into inner channel sections 32 and outer channel sections 34. It i5 noted that the inner channel sec-2S tions 32 are closely adjacent to each other which creates a localized excessive heat area and thus "warpage and over-heating problems" which this invention intends to overcome. The intermediate connector sec-tion 22 is provided with a plurality, namely three, 30 connector holes 26 which are adapted to receive con-nector bolt and washer members 17 for attachment to the engine block 15.
The lower connector section 24 is provided with a couple of connector holes 26 adapted to receive bolt 35 and washer members 17 therein for further rigid connection ~S4~

to the engine block 15.
The cylinder head modification assembly 12 consists of two major elements being 1) a main expansion transfer plate assembly 38; and 2) an exhaust port 5 expansion transfer assembly 40. The main expansion L
transfer plate assembly 3~ includes a main support body section 42; a heat transfer section 4~ integral with the main support body section 42; and connector sections 46 integral with the main support body section 10 42 and the heat transfer section 44. The main support body section 42 includes a connector support section 48 integral with an outer support portion ~0.
The heat transfer section 44 consists of three t3) inner heat transfer portions 54, each sur 15 rounded by a portion of the main support body section 42.
The plurality of connector sections 46 are each substantially identical being of oval shape hav-ing a connector hole portion 56 centrally of a con-20 nector support portion 60. Each connector hole portion 56 is provided with a central hole 57.
It is noted that the heat transfer secti~n 44 is suhstantially half or less than half the thickness of the connector sections 46 and the main support body 25 section 42 so as to allow rapid heat transfer there-through and aid in cooling of the main expansion trans-fer assembly 38.
The exhaust port expansion transfer assembly 40 is provided with a main support body 64 of irregular 30 shape integral with an anchor section 66. The anchor section 66 is substantially twice the thickness of the main support body 64 to provide rigidity thereto while the main support body 64 provides a larger than stan-dard surface area to tra~sfer expansion o~ the cylinder 35 head structure. The anchor section 66 is provided with ~S~

a central connector hole portion 56 having a central hole 57.
~ he method of preventing cylinder head war-page and over-heating of this invention involves a S slight modification of the cylinder head structura 14 shown in Figure 1 and, additionally, applying the cylinder head modification assem~ly 12 of this inven-tion thereto. The first step involved is taking the upper connector section 18 and the holes 26 as shown 10 in Figure 1 and modifying by filling an inclined up-per connector portion 68 with a epoxy or welding ma-terial as illustrated in Figure 8. After filling the sub~ect connector holes 26, the area is machined so as to present an upper flat surface indicated at 70 so as 15 to provide a continuous support to the expansion trans-fer plate assembly 38 to be mounted thereon in a man-ner to be explained.
Next, the main expansion transfer plate as-sembly 38 is placed on the upper surface adjacent the 20 connector holes 26 on the upper connector section 18 as shown in Figure 9. Next, a plurality of the bolt and washer members 17, namely three, are inserted through the respective connector hole portions 56 and central holes 57 of the connector sec~ions 46 of the main ex-25 pansion transfer assembly 38 for securing same againstthe cylinder head structure 14 and to an engine block member 15.
~ he next step is to apply the exhaust port expansion transfer assembly 40 to the intermediate con-30 nector section 22 of the main head body 16 which isshown as on top of the inner channel sections 32 of the exhaust channels 30. It is obvious that this area, with the two adjacent exhaust channe~s 3~, creates an excessive heat probl~m in this area which leads to the 35 warpage of the~aluminum cylinder head structure 14.

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Next, a bolt and washer member 17 is inserted through rthe connector hole portion 56 and central hole 57 of the anchor section 66 of the exhaust port expansion transfer assembly 40 and to an engine block member 15.
Next, the subject bolt and washer members 17 inserted into the respective main expansion transfer plate assembly 38 and the exhaust port expansion trans-fer assembly 40 are tightened through the use of a tor-que wrench to get an even torquing pressure thereon 10 being ideally 55 lbs. per square inch. The torque pressure can be varied plus or minus 5 lbs. per square inch. This is important so that the main expansion transfer plate assembly 38 and the exhaust port expan-sion transfer assembly 40 are evenly torgued downwardly 15 and provide a full contact of the undersurfaces thereof with the respective connecting areas on the cylinder head structure 14.
With this achieved, it is noted that the cy-linder head modification assembly 12 acts to 1) pro-20 vide a greatly increased contact area on the uppe~surfaces of the cylinder head structure 14 to control expansion downwardly and outwardly to either end pre-venting warpage thereof; and 2) the use of the cylinder head modification assembly 12 by being preferably con-25 structed of a high strength steel, it will not bend orwarp at the connection of the bolt and washer members as happens with the contact thereof directly with an aluminum cylinder head structure 14. Thus the cylinder head modification assembly keeps the cylinder head 30 from flexing due to power stroke forces of the engine which increases performances and eliminates cylinder wall deormation which~could cause oil consumption due to excessive crankcase pressures.
In the use and operation of the invention, it 35 is noted that the cylinder head structure 14 as il-lustrated in Figure 1 is first to be modified by filling ~254'~6;~
g the connector holes 26 on th-e upper connector section 18 as hy an epoxy or welding material as shown in Figure 8. The upper surface 70 thereof is then ma-chined to be completely horizontal in the same plane 5 as the surrounding matexial.
Next, the elements of the cylinder head modification assembly 12 being the main expansion transfer plate assembly 38 and the exhaust port ex-'F
pansion transfer assembly 40 are placed upon the re-10 spective upper surfaces of the cylinder head structure 14 as shown in Fig. 9. The rearward curvature of the back edge of the main expansion transfer plate as-sembly 38 has been machined to fit into similarly shaped .
areas of the cylinder head structure 14. Next, bolt an 15 washer members 17 are pLaced ~ithin the respective con-nector hole portions 56 and central holes ~7 of the main expansion transfer plate assembly 38 and the ex-haust port expansion transfer assembly 40 of the cylinder head modification assembly 12.
The bolt members 17 are torqued to a pre-determined desired pressure~ preferably 55 lbs. per s~uare inch, so as to anchor the inter-connected cy- -.
linder head modification assembly 12 and cylinder head structure 14 to the engine block 1~.
It is no~ed in the skematic diagram of Fig.
10 and as indica~ed by arrows 74, it is seen that the exhaust gases are to be fed outwardly through the exhaust channels 30 into a manifold structure and then to a muffle pipe system to exhaust the heat from the 30internal combustion engine. It is noted that the inner channel sections 32 are adjacent to each other, and therefore, achieve an excessive heating area indicated by an arrow 76 in the cylinder head structure 14 as shown in Fig. 10. This excessive heat is transferred to the 35cylinder neaa modification assem~ly 12 as a form of ex-pansion forces which are reversed downwardly and outwardly to either en~ of the cylinder head structure 14 to keep the same fr~m becomin~ warped.

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Also, the enlarged connector areas with the connector sections 46 of the main expansion transfer plate assembly 38 provides substantial rigidity to this overheated area to prevent the same from becoming warped 5 and the bolt and washer members 17 from becoming loose.
The preferred method of preventing cylinder head warpage and over-heating of this invention in- ~
volves the steps of: r 1)~ filling of certain connector holes sections 10 on the original cy-inder head structure 14 with an epoxy or welding material;

2) machining the area about the above filled connector hole sections on the cylinder head struc ture 14 so the same lies in a common horizontal plane lS with adjacent area;

3) applying the expansion transfer pIate assembly 38 to the cylinder head structure 14i and/or

4) applying the exhaust port expansion trans-fer assembly 40 to the cylinder head structure 14;
S) inserting bolt members 17 through the respective central connector holes in the main ex-pansion transfer plate assembly 38 and the exhaust port expansion transfer assembly 40;
6) torquing the inserted bolt members 17 25 to a desired pressure such as S5-lbs. per s~uare inch plus or minus 5 lbs.; and 7) transferring excessive expansion build up within the cylinder head structure 14 downwardly and outwardly toward either end through the cylinder 3C head structure 14.
It is seen that the method and structure of .
preventing cylinder head warpage and over-heating of an internal combustion engine as set forth in this specifi-cation is operable to achieve the desired end result 35 with the minimal amount of machine effort, special tools, ~2S~

and additional parts to be added thereto.
The main expansion transfer plat.e assembly is of a unique and unusual design of various thickness so as to achieve the expansion transfer and strengthening S characteristics with a minimum amount of expense and i.
skilled labor required. Additionally, the exhaust port expansion transfer assembly i~ operable to provide the necessary strength and expansion transfer character-istics at the area of exhaust channels which are placed 10 adjacent to each other.
This invention achieves the method of pre-venting damage to a cylinder head structures which is economical to achievei reliable in operation; easy to install; and substantially maintenance free. ._ While the invention has been described.. i~
conjunction with preferred specific embodiments thereof, it will be understood that this description is intended to illustrate and not to limit the scope of the in-vention.
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Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A method of preventing cylinder head warpage and over-heating of internal combustion engines, compris-ing:
(a) removing anchor bolt members that are holding a cylinder head structure against a cylinder block structure;
(b) applying an expansion transfer plate assembly to an area above the exhaust ports on said cylinder head structure;
(c) inserting bolt members through holes in said main expansion transfer plate assembly so as to anchor same against said cylinder head structure and to said engine block structure; and (d) torquing said bolt members to an even desired pressure to clamp said expansion transfer plate assembly against said cylinder head structure;
whereby said expansion transfer plate assembly applies a large surface area to an upper surface of said cylinder head structure to control expansion and to prevent warpage thereof.

2. A method of preventing warping and over-heating of cylinder head structures as described in claim 1, includ-ing:
(a) applying an exhaust port expansion transfer assem-bly to an intermediate surface of said cylinder head structure;
(b) inserting a bolt member through a hole in said exhaust port expansion transfer assembly to anchor same firmly against said cylinder head structure;
whereby said exhaust port expansion transfer assem-bly adds increased surface area to a portion of said cylinder head structure which transfer expansion therefrom to prevent warpage thereof.

3. A method of preventing warping and over-heating of cylinder head structures as described in claim 1, including:
(a) filling of connector hole sections in said cylinder head structures with a rigid material; and (b) machining the areas of the filled holes so as to make the same in a common horizontal plane with adjacent areas.

4. A method of preventing cylinder head warpage and over-heating of internal combustion engines, comprising:
(a) removing anchor bolt members from connector holes in an upper connector section that are holding a cylinder head structure against a cylinder block structure;
(b) filling said connector holes with a rigid material;
(c) machining the area of said connector holes and said upper connector section to present same in a common plane;
(d) applying an expansion transfer plate assembly hav-ing a large surface area to said upper connector section; and (e) securing said expansion transfer plate assembly against said upper connector section;
whereby said expansion transfer plate assembly transfers heat from said cylinder head structure at said upper connector section to control expansion and prevent warpage of said cylinder head structure.

5. A method of preventing warpage and over-heating of cylinder head structure as described in claim 4, includ-ing (a) applying an exhaust port expansion transfer assem-bly to an intermediate connector section above ex-haust channels on said cylinder head structure; and (b) securing said exhaust port expansion transfer as-sembly against said intermediate connector section;
whereby said exhaust port expansion transfer assembly transfers heat from said intermediate connector section to control expansion and prevent warpage of said cylinder head structure.

6. A method of preventing warpage and-over-heating of cylinder head structures as described in claim 4, in-cluding:
(a) torquing said expansion transfer assembly and said exhaust port expansion transfer assembly against said cylinder head structure to a pressure recom-mended by the subject engine manufacturer for torquing said cylinder head structure.

7. A method of preventing cylinder head warpage and over-heating of internal combustion engines, compris-ing (a) applying an exhaust port expansion transfer assem-bly to an intermediate connector section above exhaust channels on said cylinder head structure;
and (b) securing said exhaust port expansion transfer as-sembly against said intermediate connector section;
whereby said exhaust port expansion transfer assembly transfers heat from said intermediate connector section to control expansion and prevent warpage of said cylinder head structure.